title: Accelerated aging of fasted Drosophila. Preservation of physiological function and cellular fine structure by thiazolidine carboxylic acid (TCA).
abstract: Thiazolidine carboxylic acid (TCA) is a natural liver metabolite whose Mg-salt increased lifespan of flies and mice (Miquel and Economos, 1979, Exp. Geront. 14: 279). We studied the physiological and cellular fine structural effects of various concentrations of TCA in the food of male Drosophila. Flies on 0.3% TCA at 27 degrees C had a reduced oxygen consumption rate (about 20% less than controls) at 3 wks of age while their mating capacity and speed of mating were preserved; the flies lived in various experiments 20-30% longer than controls. Apparently TCA improved the metabolic efficiency of the flies (possibly from less "waste" of energy due to improved mitochondrial coupling). However, flies on 0.9% TCA had a reduced mating capacity and lifespan (:toxicity) while at 0.1% TCA was ineffective. A similar dose-response relationship was found in young flies treated with TCA for 1 week and then deprived of food and water, a procedure found to induce accelerated physiological aging. TCA at the 0.3% and 0.6% level reduced the speed of development and the size of the enclosed flies. Electron microscopic investigation of wing muscle showed that 0.3% TCA had a protective effect on cellular fine structure. Though in starved controls (40% survivors after 24 hours of starvation) there was a total absence of glycogen granules, and a striking shrinkage and densification of mitochondria, TCA to a large extent protected muscle cells from these effects of starvation.
mesh_terms: D000375:Aging / Q000187:drug effects*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004331:Drosophila melanogaster; D005215:Fasting; D005260:Female; D006003:Glycogen / Q000378:metabolism; D008297:Male; D009132:Muscles / Q000187:drug effects / Q000648:ultrastructure; D010101:Oxygen Consumption / Q000187:drug effects; D012726:Sexual Behavior, Animal / Q000187:drug effects; D013844:Thiazoles / Q000494:pharmacology*; D053778:Thiazolidines
chemical_list: D000975:Antioxidants; D013844:Thiazoles; D053778:Thiazolidines; D006003:Glycogen; C003438:thiazolidine-4-carboxylic acid